Automobile alignment gauge



Sept. 12, 1950 R. D. SMITH AUTOMOBILE ALIGNMENT GAUGE 3 Sheets-Sheet 1 Filed Feb. 7, 1946 PIE-5 FIE-.2

INVENTOR. BY ROY SMITH Sept. 12, 1950 R. D. SMITH 2,522,066

AUTOMOBILE ALIGNMENT GAUGE Filed Feb. '7, 1946 3 Sheets-Sheet 2 IN VEN TOR.

ROY D. 5mm

Sept. 12, 1950 Filed Feb. 7, 1946 R. D. SMITH 2,522,066

AUTOMOBILE ALIGNMENT GAUGE 3 Sheets-Sheet 3 INVENTOR. BY ROY D. SMITH Patented Sept. 12, 1950 .wmiosm ALIG MENT GAUGE,

Roy D. Smith. 'Mertzon, Tex.,assignor to Bee- Line Company. Scott County, Iowa, at ccpartner'ship ,Appiication February 7, 1946, Serial No. 646,009

a 5 Claims. (01. 33-20315) The present invention relatesto a method of and apparatus for measuring the relative align ment of the dirigiblewheels of a motor vehicle'in order to produce the best results. Itisparticw larly useful in checking the alignment conditions of a motor vehicle in which one or both of the front wheels havelateral wobble.

Among the objects of this invention are the provision of an improved apparatus for checking the alignment of motor vehicle wheels; the provision of a newv mode of operation which will elimia nate errors which are common in-connection with methods of checking'which are now prevalent'in this art; and such further objects; advantages, and capabilities as will hereafter appear and as are inherent in the apparatus and method disclosed herein; My invention further resides in the combination, construction, and arrangementof parts illustrated in the accompany- Figs. 2 and 3 represent side elevations of the 4 front wheels of a motor vehicle, of which Fig. 2 may be considered as representing the right wheel and Fig. 3the left wheel; A

4 represents a plan view of the front wheels of a motor vehicle withthe points of wheel runout indicated by the arrows 39; l

Fig. 5 represents a plan view of the front wheels and axle of avehicle, in a position for running straight ahead, with the gauging apparatus in position for testing toe-in and toe-out;

Fig. 6 represents a view similar to 'thatof Fig. 5 except that the wheels are inpositionfor the making of a right hand turn;

Fig. '7 represents a side elevation of l a vehicle wheel with a gauge attached for a checking operation; 1 1

Fig. 8 representsa partial sectional elevation substantially along the plane indicated by the line 8-8, Fig. 7, the wheel beingindicated in a vertical position;

camber; r

Fig- 10 represents a side elevation of the camber-gauging-element shown in Fig. 7;

mechanism is held to the tire;

. 2 v v Figpll represents a section of the cambergauging element as if taken substantially on the planeindicated by' the line! Fig. 10';

"Fig. 12 represents apartial section taken substantially along the plane indicated by the line 12 Fig. "7, the'same showing how the gaug Fig. 13 represents an elevation of the checking apparatus shown in Fig. 7, taken in the. direction of the arrow [3 that figure; and

Fig-14 represents a sectional elevation of the gauging apparatus shown inFi'g 'l, taken sub stantially' along the plane indicated by the line M -14, Fig. 12.

I, j Reference willnow be made in greater detail to the annexed drawingsforfa more complete description 'of this invention. In this apparatus, a rectangular'elongated bar or body I is secured to a pair of U-"shaped brackets 2 by means of bolts 3. The arms of these brackets have openings therethroughfor the reception of the bolts 4, each provided at "one end with a collar tcbe engaged by'"'a spring 5', surrounding the bolt 4, the sec'cndendpressing against the upper arm of the bracket, asshown atB. This forces the bolt downwardly until it 'is stopped by the other arm .1 of the bracket 2. As shown clearly in Fig.

into a screw-threaded opening extending lon gitudin'allyinto' one end of the post 8. n

The boltsl serve as legs to supportthe bar I andassociated parts abovethe floor or supporting amount of caster, it is necessary for the legs 4'to right or left. This actionis made possible by the r Fig. 9 represents a view similar'to that of Fig. 8 but with the wheel tilted to show excessive I caster action. Were it not for the upward yielding: ofthe-legs,"they' would be forced away from the wheels when'they 'areturned to right left." An 'slia;ped r v wheel andilthe other arm inside of the wheel, as

; shownclearly on-sheets} and-310i the drawings.

A bar in has, in one "endthereof, an opening which is: slightly larger than the bar 9, which opening serves to receive theend of the latter bar; asshown .clearly 'in' Figs. 7 and .12. The otherend 'of the bar Hi has a screw-threaded opening therethrough forthe reception of the If'the wheel has a" considerable ocl B'ha'sone arm in front of the bolt II which engages the upper end portion of the post 8 and serves, when screwed in, to push the post 8 toward the wheel as far as is permitted by the rest of the apparatus, about to be explained.

As shown clearly in Figs. 8 and 9, the arm of bar 9 which is inside of the wheel fits closely within the angle between thel tire-aridthe support 12; The bar 9' can therefore not be moved outwardly because stopped by the tire and cannot swing downwardly because stopped by the support I2. It is thefore a rigid support for-the bar Ii) and enables the screw or bolt H to push the post 8 inwardly as far as it can go.-':However,= there is on the bar I an abutment l3 and-on th'e bar [6 abutments M and i which definitely position the apparatus with relation to lthe-tiree The bar I6 is immovably connected to the bar I, either by means of a screw or by beingwelded thereto, and therefore any rotation of the latter, r

bwreason of w-rningnthe screwzz h luintov .the i'bar Hi3: would! rtBTld'itO a-causei movemente ofirthe supper end of theba-r iifi-towardithatire. ufiowevercfthis is; preventedwby engag'ement of r=therabutinent i l 5 with the tireias shown :in Fig. 7 Theithreeiabutments r113; ll-,:-fl5cformr za triangle andfitis-afiproximately at therdente'r of thef figure'tofxithis triangle that the-force-of. screw: l --lristransmitted tosthe-post ,8; .q lherefore, the pl'essurezupon'th'ese three abutments- .is; substantially zehualir and-Z in w ard,;movement ofrthei-post andsbars trand rilli in ist w he' e sincel-tirestdifferrirr size it isinecessaryito have the abutments l3, l4, l5 relatively adjustable; andgtlg -is. lS PKQVidBdgfOI: byzmakingfitheabutments I 3gan l5, adjustable-alongtha bars brand 5 I5. block: i i-sis positioned withrelation':toctheilower; end ofethe poster; ban lfin-by a pirr l:81andva=:bolt [Spas ShOWILiIL-Eigfill; A pivotmember pivot allyconnectst-the blockr M' -to the :block 51 T." In theuppenendof therblock 2] ,"asshoWmimFfigrll' isra-l'evel; 22; the i use of wvhich ;willbe lPIGSGH'bl-Y explained; In; the lower end Qfrthfirblolill :is a screwlz-hwhich :is used forsadiusting lthecblock z hwith'relation to'ithe blockaflr lQnzt'h'e end or thissscrew 12:3 rid-secured a head "\flabyvmeansii'of which the screwv-mayi bet turnedi forradjus'tin'g .the blooks relativelyrz The heada l isugraduated; as shown i-n:-Cl1"ig-.- P I0, for; use inf; measuring car'n berz amd-;caster;; -:The: graduationsronzthehead 24 cooperate with: annindi'catortifi on: the' blo'ck 5.2L With tthea-wheels set;;for running-:straightzahe'ad, the-. head 1 ore-knob 2 24 is r turnedruntil the: leveliszz indicates zero inclinationgand the amount :of

camber: ris read fromwthe .agraduationson the face of thehead-v :A sleeve'fzfiris adiustablymounted onnthetbar r andmarniesa laterallyaproje'cting. arm"?! whichisadjustedmot.en a e;thesback.facerofathextire while:

planemof arms- I rand H B," engages :the-zfront' face of! the. tire; .The'se twoarms:ilztandflflzitherefore definitelyrpositionithe bar I- withrelationatmthe tire; Qnathezarmi-zflriscslidablyv mountedia' sleeve 219m which rhas anarmn30 :pr'ojecting forwardly therefrom. A socket 3| connected to the proof protractor ,-32 are .'graduated;inr angular- ,meas- I The sockets 3 I: mayrbe the pointers point slightly to the rear of the zero lines iattheimiddle of these sectors, as shown in Fig. 5. alternative method of measuring toe-in or toe-out of'vehicle-wheels is shown in Fig. 5 by the dotted lines H and 42. In this method, a measuringscale -.graduated in inches and fractions thereof is used to measure the distance be- *twee'n'th bars I. The distances should be measured substantially in vertical planes tangent to thettreadsiof th'e ztireszs Theimeasurement having been .:taken-at.r theifront; ofrthe tires; the";meas'ur-, ingcfscalea is then gmoved 1130" the i rearward portion of ether bar's l l and: a. "similar measurement taken alongiline :42; If'iheTYdiStaIICBiS- greaterzalong line '42 than along'lin'e tl-g theivehicle wheels are toed in an amountrequal to thexdifferenceainrthe two measurements.

wffinxorfderato determineilif there is whe elwwobble ahdui'f-so, ithe pointrof rgreate'st lwobble; 01 runout, F scribers. are set onxthe" supports l 2, '.-when theiffiintl axle of the vehicle-i has been rais'ed to lift rthe rwheel's 7 off. lth'e" supporting meansi' ia-nd'; withxthe wheelsrotating, the s'cribe'ts are moved in until' -the crayon or other marki'ri'gmateriai 38 contacts!the'ftireiwhereby a. mark 3'9"is"placed on thefsi'dei-wall of the tire. The marks 69 indi cate what part of thei'tires have the greatest out ward 'imotion. These marks are then :.m'a=de-use' of aim determining the relative wheel alignment ofithezwheelsr-as hereinafter "set-fortl 1.' Q'Method'ofiopez 'atio gz I ,v The method ofeoperatidrir-With thel-pres'ent' mechanism will merit the describedv suitable means 40, which may include jackspis used: for :r.aising "the: rwheels 01f -,fromthe; "supporting means tleWhic-h may .bea 'fifl01'i,OI"- -blOBkS: placed under the'iwheels. ,If :the: wheels ;are 'not-i-a'lready setfor -.running straight' r-ahead, they areztnext s'et;this :position. ',-A-,-scriber 311 is :themplacedon rthe support; l2v with the markingrelement 38- a little distance from-thetiredwhich is then 'set' in rotation about itsspindie; :Thescriber is. vthen graduallyrxmoved (toward! the tiresuntil the. latter contacts the markingnelement 38', when v.a line- 39 ;.will :be-.--scribedon ,the rtire sidezwalh- {If-Ithe wheel has 1 no wobble, this .line Will: be. continu- 011s about'thetire'butxif there i's'i an'y wobble,- the line 39' wi'llube a=shorteline orailorigerline, depending 11113011 hows-much the wheel :is :JOllt Of true. ':-liigs-.i-2. and 13 show substantially the same amount of Wobble :Qf' the'TightLandi leftwfront whee1sof..-a:motor"vehicle; 4 5* Afterr-scribing a' reference markr39 at the point of greatest wheel wobble on the side wall- 0f eachtire, the; axle isr lowered: to? cause the whels torrest on'tth'e ss'upporting vniean's l2,- with -the mark E39 raonsone :wheel toward the. "front of the vehicle and the correspondin mark i'ifir'owthe other cwheel otoward ='z'the- 1 reari of athe vehicle.

, Sincerfew vehicle wlreels runtrueyit 'follows that when usin other gauging equipment, the whe'el' wobbl'ermayrfcause errors sin 1 testing w-he'el alignment. :Wben the-.rzpresent :metho'di is aised; I? the that true and accurate readings may be obtained.

: Eig. 4= showsthe use of this method, thezline 39 :ofnthe right handwheelbein -:in front of the :axle and. at the same elevations-ironic;the,supportx i. wh e a t epppos tesi of t eatr fh clellihe line 39 011 :;17118118fl1h3ghd tireixisto the :t aro t ee le and t e s m t zf em-th support; l2. e, the de on of the wheel from true position does"not' give a greater or less distance between the wheels than the true reading; Therefore, i when readings are, ini'ade with the wheels set .as indicated, there will not be a distorted reading, as would be the case if the wheels were not set as indicated herein. For example, if the scribed lines were both in front of the axle, then there would be a greater reading between the wheels than the true reading. On the other hand, if the scribed lines were both to the rear of the axle, then the distance between the tires, in front of the axle, would be less than the correct reading. It therefore follows that, if the wheels are in the positions indicated in Fig. 4, that is, with one scribed line in front of the axle and the other to the rear of the axle, and the gauging apparatus is applied, as indicated in Fig. 5, it would be possible to get a true reading, rather than one distorted by the wheel wobble.

It should be noted, in connection with the discussion just preceding, that this operation tends to eliminate errors when making toe-in readings. Since the points of maximum wheel wobble are placed in a horizontal position, the result is that the wobble has no effect in a vertical plane when gauging for the camber angle.

If it were to be found that one wheel was running perfectly true, with no wobble or run-out,

and the other wheel wobbled a substantial amount, correction can be made by noting the amount of wobble and compensating for it in making a toe-in reading by adding or subtracting one degree for each half inch /2") of wobble, with conventional sizes of automobile wheels.

It will of course be understood that the specific description of structure set forth above may be departed from without departing from the spirit of this invention as disclosed herein and as defined in the appended claims.

Having now described my invention, I claim:

1. In a wheel-checking apparatus, in combination, a pair of wheel-gauging units, one connected to each of the oppositely positioned wheels 6 *againsttha tire-with substantially equal pressure, meansfor holding 'the lastim'entio'ned means againstbeing 1 presse'dfialway' from the tire, and means connected to said bars for measuring the angular relations of the tires on the two ends of the axle, indifferent positions of turning 'adjustm 1 i 3. In apparatus forfi'clrecking the 'geometryof the dirigible wheels of a motor vehicle, a pair of bars, one of them substantially horizontal and the second one's'ubstantially vertical, secured together g 'm a plane and at substantially a right angle to each other, abutments secured to-said bars to bear against the side wall of a tire, one of said abutments being located approximately at the junction of said bars and two other abutments carried by said bars remote from said junction, legs extending downwardly from one of said bars to support the weight thereof and of the parts connected thereto, an L-shaped rod, one arm of which is located at the inner side of the wheel adjacent its point of contact with the wheel-supporting surface, the other arm being located forwardly of the wheel and extending transversely thereof close to the wheel, a substantially vertical pressure bar movably connected to the second arm of said L-shaped rod, a substantially vertical post rising from the substantially horizontal one of said pair of connected bars, and the substantially vertical bar connected to th second arm of said rod having a screw extending therethrough, operatively engaging said vertical post, the abutments connected to said pair of bars positioning said pair of bars parallel to a wheel in connection with which the apparatus is used.

4. In an apparatus of the class indicated, a mechanism to be placed at the side of a vehicle wheel for use in checking the steering geometry of the vehicle, comprising a bar which is substantially horizontal during use, a second bar secured to the first bar and extending substantially vertically therefrom, abutments on said bars to hold them a fixed distance from the wheel, legs connected to the horizontal bar to support the same at the side ofthe wheel, and means for pressing said bars and abutments toward the wheel, said legs comprising a broadly U-shaped frame having a vertically movable supporting tact with the surface on which the wheel is of a vehicle, each unit comprising two bars rigidly connected at a right angle to each other, supports connected to one of said bars and adapted to rest on a floor or other supporting means to support said bar alongside of a wheel, tire-engaging abutments on said bars adapted to be pressed against the side wall of the tire, means for pressing the abutments against the tire with substantially equal pressure, means for holding the last mentioned means against being pressed away from the tire, and means connected to the two bars provided with supports for measuring the distance between the tires carried by the vehicle axle, atopposite sides of the vehicle.

2. In a wheel-checking apparatus, in combination, a pair of bars rigidly connected at a right angle to each other, supports connected to one of said bars and adapted to rest on a floor or other supporting means to support said bar alongside of a wheel, tire-engaging'abutments on said bars adapted to be pressed against the side wall of the tire, means for pressing the abutments supported.

5. Measuring means, for use with a motor vehicle to measure the angles connected with the steering of the vehicle, comprising a pair of substantially identical members to be applied to the outer lateral faces of the dirigible wheels of a vehicle and a longitudinally extensible and front thereof, a sleeve adjustalble along the first mentioned bar, a transversely extending bar adjacent the opposite end of the first mentioned bar at the side of the wheel, a sleeve adjustable along the horizontally extending bar, resiliently yieldable legs supporting the first mentioned bar at the side of the wheel and permitting vertical motion thereof as the wheel is turned from right vehicle are turned: lsttemlly.

taleftor vice versa,7 a; :gra,dua;ted= seetbr-conneeted to" the last: mentioned sleeve and: swinging latverztlly withwhe' wheel -with= which: it. is assuciated, and. a; pointer pivotally connected to the sector and; rigidly connected-tmamendxpbntion of-the extensible w bar whereby i te .cause swingingof the pointer over the sector as the wheels ofwthe may DL'iSMITH.

'REFERENGESfiITED v 'The following references are (if ireco'rdfin the file of 3 this patent:

' -UNITED STATES PATENTS- Number Number Great Britain ""Ma,y 1,:1939 

